The invention relates to a protective sheath for a fusion or adhesive optical waveguides splice. The sheath comprises a fusion bonding sleeve and a shrinkable sleeve surrounding the splice, and an oblong support arranged between the bonding sleeve and shrinkable sleeve.
Fusion or adhesive bonding of optical-fibers has been finding increasing application in practice for connecting optical waveguides. Because the fibers have to be stripped of their plastic sheathing at the splice, the splice is mechanically weak and hence requires special protection.
In a known method of protection, the splice is embedded in cast resin. However, this method has the disadvantage that it is time-consuming. Time must be allowed for heating and curing the resin.
In another known method a spliced joint is embedded in a fusion bonding agent by heating. A shrinkable sleeve is arranged over the fusion bonding agent. In addition, a steel pin, which mechanically reinforces the protective sheath, is placed between the fusion bonding sleeve and the shrinkable sleeve. This, however, gives rise to the disadvantage that the fibers are pressed so strongly against the steel pin by the contraction of the shrinkable sleeve that mechanical damage or additional losses can occur.